arch

arch is a Noun

Definition:

[1] Any part of a curved line.

[2] Usually a curved member made up of separate wedge-shaped solids, with the joints between them disposed in the direction of the radii of the curve; used to support the wall or other weight above an opening. In this sense arches are segmental, round (i. e., semicircular), or pointed.

[3] A flat arch is a member constructed of stones cut into wedges or other shapes so as to support each other without rising in a curve.

[4] Any place covered by an arch; an archway; as, to pass into the arch of a bridge.

[5] Any curvature in the form of an arch; as, the arch of the aorta. "Colors of the showery arch." Milton. Triumphal arch, a monumental structure resembling an arched gateway, with one or more passages, erected to commemorate a triumph.